RIBBING DISEASE (MULTIPLE DIAPHYSEAL SCLEROSIS) - IMAGING AND DIFFERENTIAL-DIAGNOSIS

OBJECTIVE. This study describes the clinical presentation and the cour se of Ribbing disease in six patients and illustrates imaging features on plain radiography, conventional and computed tomography, and Tc-99 m-methylene diphosphonate bone scans. MATERIALS AND METHODS. Between 1 982 and 1990, six female patients presented with painful bony lesions that were believed to be Ribbing disease. Ten bones were affected: bot h tibiae in three patients, a unilateral tibia in one, both femora in one, and a unilateral femur in one. Plain radiographs and either conve ntional or computed tomography were available for all patients and Tc- 99m-methylene diphosphonate bone scans, for five patients. All patient s underwent open biopsy and/or surgical decompression. RESULTS. The di agnosis was reached in all patients through a combination of clinical findings (lack of systemic signs of infection or laboratory values sug gesting metabolic bone disease), imaging, histologic evaluation, and s pecimen cultures. Radiographs and tomographic studies showed benign-ap pearing endosteal and periosteal cortical thickening. Intense uptake o f radionuclide tracer was confined to the shaft of all involved bones. All pathologic specimens revealed nonspecific changes that included a slow increase in the mass of cortical and endosteal bone. These speci mens also assisted in excluding neoplastic or infectious causes for th e new bone formation. CONCLUSION. Ribbing disease is a rare disorder t hat, on imaging studies, may simulate stress fracture, chronic infecti on, bone-forming neoplasia, or a systemic metabolic or endocrine disor der. Clinical and imaging features may suggest the correct diagnosis.